As a rental company this is a question we are asked time and time again. The question usually arises when clients need Windows based computers and laptops either for standard training and office use or for complex processing.
In the past, 4GB of RAM seemed to be more than sufficient to run Windows XP or Windows 7 for any Office package or Web based training. Even graphics and video programs would run without the dreaded paging of memory to hard drive. However as 64 bit programs started to take full advantage of RAM beyond the 32bit limit of approx 3GB, the amount of RAM available starts to have an appreciable affect on performance.
Take the simple process of updating Windows 7 (64bit). We have standard Lenovo laptops with 4GB of RAM running the same 64bit version of Windows 7 as our 6 core high end workstations with 32GB of RAM. Updating the laptops takes 2-3x the time it takes the 6 core workstations, checking and updating from the same “last update” time, so installing the same number of updates.
As a quick test we updated two identical laptops with the same OS image, one with the standard 4GB of RAM and the other upgraded to 8GB of RAM. The maximum RAM in use with the 4GB of RAM was 2.3GB and the maximum RAM in use with the 8GB RAM was 2.9GB. The 8GB RAM laptop completed updating 20% quicker. Interesting? Updating one of our Workstations with 32GB RAM used a maximum of 6GB of RAM during the searching for updates phase and completed the update nearly 3 times as fast however these workstation also have SSDs.
So even updating Windows 7 speeds up when the memory is increased from 4GB to 8GB.
So the advice as of 2015 would be 4GB as a bare minimum, but best to have 8GB (all our new models have 8GB minimum) even for standard office use.
If the application is more demanding then investigate the software developers website and find the hardware requirements, then double the suggested RAM – sometimes 64GB seems a little cramped!